3rd French conference on acoustics
J. Phys. IV France 04 (1994) C5-89-C5-92
Identification des fréquences caracteristiques dans la transmission acoustique d'une coque finie raidieG. GUERIN1, C. LESUEUR1, F. PEDROLA2 and C. CACCIOLATI1
1 Laboratoire Vibrations-Acoustique, Bâtiment 303, INSA de Lyon, 20 Avenue Albert Einstein, 69621 Villeurbanne cedex, France
2 Aérospatiale Avions, BP. MO1 42/2, 31060 Toulouse cedex 3, France
Computer codes for predicting noise level inside aircrafts point out some typical frequencies in noise reduction results. These phenomena are studied in this paper with help of a comparison between numerical and experimental results about a shell representing a part of Concorde fuselage ; this one is excited by plane waves with two incidences, or by a reverberant field. Numerical results about Airbus aircrafts are also used. We show the influence of the internal volume eigen-frequencies, and of frequencies assigned to the equivalent panels between frames and stringers ; the slopes of NR versus frequency are also interpreted.
© EDP Sciences 1994